The present invention relates to the harvesting of blood vessels and, more particularly, to methods and apparatus for endoscopic dissection and retraction of sections of blood vessels, such as saphenous veins, for use as a coronary artery bypass graft.
It is common during various surgical procedures, and most particularly during coronary artery bypass grafting (CABG), to remove or xe2x80x9charvestxe2x80x9d a blood vessel or vessel section, such as an artery or vein, from its natural location in a patient""s body and to use it elsewhere in the body. In CABG surgery, the blood vessel is used to form a bypass between an arterial blood source and the coronary artery that is to be bypassed. Often an artery proximate the heart, such as one of the internal mammary arteries, can be used as the bypass graft, although the saphenous veins in the legs, or a radial artery in an arm can also be used as well.
The conventional surgical procedure used to harvest a section of the saphenous vein, or the like, for use in the CABG surgery, is generally very traumatic to a patient. The procedure involves making a continuous incision in the leg for the full length of the desired vein section in order to provide adequate exposure for visualizing the vein and for introducing surgical instruments to sever, cauterize and ligate the tissue and side branches of the vein. The incision must then be closed by suturing or stapling along its length. Significant complications from this procedure may arise, such as infections, nerve damage, and hematomas. This type of surgical procedure is also known to produce undesirably scarring and can increase the patient""s recovery time and hospital stay; thus adding to the overall cost of the CABG procedure.
In an attempt to overcome these problems, less-invasive techniques for harvesting blood vessels have been developed which employ only two small incisions, generally one at each end of the section of vessel to be removed. Primary dissection occurs by introduction of one or more surgical instruments through a first incision to create a working space and separate the vein from the surrounding tissue. Then further instruments are introduced into the generally limited working space to dissect the blood vessel from the connective tissue surrounding the section to be harvested. The side branches of the blood vessel are also clipped and/or cauterized. In order to remove the desired section of the blood vessel, a second small incision, or stab wound, is made at the distal end thereof and the distal end of the blood vessel section is ligated. The proximal end of the blood vessel section is then also ligated, thereby allowing the desired section to be completely removed through the first incision. An endoscopic instrument is generally required for such a procedure to enhance visualization of the vessel and the surrounding tissue and to properly position the surgical instrument. Example of such endoscopic instruments for harvesting blood vessels are shown in U.S. Pat. No. 6,193,653 to Evans et al. and U.S. Pat. No. 6,019,771 to Bennett et al.
Even though these less invasive techniques reduce the overall length of the incision, the trauma to the blood vessel section, the surrounding tissue and to the patient can still be severe. In particular, the repeated introduction of a plurality of surgical instruments through the incision into the enlarged space between the patient""s skin and vein may also cause added irritation, damage and trauma to the vessel. Damage to the blood vessel or a side branch of the vessel is undesirable since the damage to the harvested section of the vessel must be repaired before it can be used as a graft and the potential for subsequent failure of the graft is increased.
Accordingly, it would be desirable to have a vessel harvesting procedure that can be carried out in a manner that reduces the trauma to the patient by minimizing the number of surgical instruments that must be inserted into the patient""s body, by more rapidly and less traumatically detaching the blood vessel from surrounding tissue on all sides, and by providing a harvesting device and procedure that provides for more precise manipulation of the blood vessel by a surgeon.
The present invention provides an endoscopic apparatus for harvesting blood vessels which has an endoscopic barrel including a plurality of lumens, one of the lumens being dimensioned for receiving an endoscope. A handle is disposed at a proximal end of the endoscopic barrel and at least one integrated means for dissecting and cauterizing a blood vessel extends from a distal end of the endoscopic barrel.
In a preferred embodiment, the at least one integrated means comprises two fingers preferably having distal curved ends. More particularly, one of the fingers defines an inner finger and the other finger defines an outer finger such that, when the fingers are axially aligned, the inner and outer fingers form a shear plane therebetween for severing and cauterizing tissue, such as a blood vessel.
The movement of each finger is independently controlled by a control mechanism within the handle. The control mechanism includes, amongst other components, a control rod extending from the handle to each respective finger such that movement of the control mechanism between a first position and a second position produces a predetermined movement of the respective finger.